Long range target identification, e.g., using laser detection and ranging (LADAR), plays an important role in defenses and space awareness.
Synthetic aperture imaging is an important technique that allows obtaining a high-resolution image of a target beyond what the real optical aperture could provide. For LADAR, synthetic aperture imaging is typically divided into two regimes. Forward (or traditional) Synthetic Aperture Imaging LADAR (SAL) assumes that a target is static and the LADAR is moving, where the movement provides a (synthetic) aperture capture. Inverse SAL (ISAL) assumes that the LADAR is static and that the target is rotating relative to the LADAR, thereby creating multiple look angles that are the equivalent of a large (synthetic) aperture capture.
In each case, motions of the static component are usually outside of the imaging process and yield an error in the reconstruction. However, such error is often unacceptable where high accuracy is desirable, such as during air-to-air surveillance and/or during combat, where both the target and the LADAR are moving and there is also additional target rotation.